Railway traffic controlling apparatus



Fgb. l9, 1952 c, w, FAlLoR 2,586,458

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed NOV. '28, 1947 8 Sheets-Sheet 2 813-17 16 fi 5 18 I 6717 -75 NEH 2L I 510012 i fl 80 81 Wsz Lampl' 1% 82 I 0,- 6e T I I? \REB c I nx 'l B 44 55 B i 76 75 IV I B B 4 W7 WEB 38 Char Wlzzilop BY 4 H15 HTTORNEY C. W. F AILOR RAILWAY TRAFFIC CONTROLLING APPARATUS Feb. 19, 1952 8 Sheets-Sheet 7 Filed Nov. 28, 1947 E 1 W -1 5 1 5 4 a n 4 .4 5 ,v m F H 7 7 1 LE. "P1 I Z 3 w g D "1B lllllllllllllllllllll II I w l|l|ll|J- 6 Z H 3 M DN B M. m m MN 6 m H 5 .1 MM Hmm m B y i L 4?, a P P B 4 I. wmfim fl w m w M5 7 M15 0 i 6 1 Fig I JNVENTOR. Charles W Failoz 4 HIS 47TORIVEY Feb. 19, 1952 8 Sheets-Sheet 8 Filed Nov. 28, 1947 ESLH aRH H' 3am) ZdPZ NW p I P g I 9 I 1 Nw 8 a a w, 2 M B rB 7 M lllllll ll I I- win 6 it 6 I S H k P W W E E JNVENTOR. 011327 WFailaI' BY HIS ATTORNEY Patented Feb. 19, 1952 RAILWAY TRAFFIC CONTROLLING APPARATUS Charles W. Failor, Forest Hills, Pa., assignor to Westinghouse Air Brake Company, a corporation of Pennsylvania Application November 28, 1947, Serial No. 788,586

18 Claims.

My invention relates to railway traflic controlling apparatus, and particularly to the type known as trafiic locking apparatus which requires joint action by persons at two different control stations for manually controlling traflic move-ff;

ments in both directions over a stretch of railway track.

Each of the two control stations may be provided with an interlocking machine, and each of the interlocking machines may be equipped with 'I a traffic lever which is mechanically interlocked with a signal lever which controls a signal for governing traffic movements into the corresponing end. of the stretch of railway track.

One feature of my invention is the provision of novel and improved means for electrically controlling a traffic lever for each of such two control stations by the traffic lever at the other control station and by trafiic conditions on the stretch of track.

Another feature of my invention is the provision of novel and improved means, including the trafiic controlling apparatus of my invention, for controlling an electric lock for a track switch at an intermediate point in the stretch of track.

I shall describe four forms of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

In the accompanying drawings, Figs. 1a and 1b, when placed side by side with Fig. let on the left, constitute a diagrammatic view showing one form of apparatus embodying my invention, in which polar stick trafiic relays and trafiic lever lock relays are controlled in series by traffic control circuits, and in which the trafiic control circuits are controlled by normal and reverse stick relays controlled by the traffic levers in conjunction with normal and reverse contacts of the polar stick traflic relays; Figs. 2a and 2b, when placed side by side with Fig. 2a on the left, constitute a diagrammatic view showing a modified form of the apparatus of Figs. la and 1b, in which an electric lock for each of the trafiic levers is controlled in part by code transmitting means at the opposite end of the stretch of track; Figs. 3a and 3b, when placed side by side with Fig. 3a on the left, constitute a diagrammatic view showing another modified form of the apparatus of Figs.

la and 1b, by which an electric switch lock may be manually controlled from either end of the stretch of track over the traffic control circuits, or may be automatically controlled; and Figs. 4a and 4b, when placed side by side with Fig. 4a on the left, constitute a diagrammatic View 2 showing a modified form of the apparatus of Figs. 3a and 3b for energizing a switchlock con- 'trol relay from one end orthe other of the stretch of track by code controlled means.

Similar reference characters refer to similar parts in each of the views.

In each of the views, contacts operated by'the various relays or other devices are identified by numbers, such numbers having distinguishing prefixes from which they are separated by a dash when the contacts are shown apart from the relay from which they are operated. The prefix for each of these contact numbers comprises the reference character for the relay by which the contact is operated. For example, contact ZEF-Bl in the control circuit for relay 4EH in the central portion of Fig.'1a is identified by the number 81 separated by a dash from the prefix ZEF which is the reference character for relay 2EF by which this contact is operated.

In order to simplify the drawings, each track, comprising two parallel series of track rails,- is represented by a single line. I I

Referring first to Figs. 1a and 1b, astretch of single track railway X is shown extending-between two interlocking layouts, one of which includes a-switch I2 and signals 4L and 4R, and the other of which includes a switch 'IZ and signals 8L and 8R. A pair of intermediate automatic signals MW and 42E is located between these two interlocking layouts.

Track X is divided by insulated joints 3 to form sections 0a, a-b, bc, cd, d-e and eh. Each of these track sections is provided with a track circuit including a suitable source of current, such as a battery 5, connected across the rails adjacent one end of the section, and a track relay, designated by the reference character TR with a distinguishing numerical prefix, connected across the rails adjacent theopposite end of the section.- Relays MTR, 4TB, 8TR and 08TH. are of the neutral type, whereas relays 4 lTR-and AZTR, are of the polarized type.

Trafiic movements toward the left, 'as shown in the drawings, which I shall assume is the westbound direction, are governed by signals 4L, MW and 8L, Whereas traffic movements in the opposite or eastbound direction are governed by signals 8R, 42E and 4R. These signals may be of any suitable design, such, for example, as the color lighttype, comprising a green or proceed lamp G, a yellow or caution lamp Y, and a.red or stop lamp R. as shown in the drawings.

Signal 4B is controlled by a neutral home relay 431-1 and by a polarized signal relayAEI-I. .Relay lRH is controlled by a signal lever 4V and by a reverse traffic repeater relay ZEF and by relay 4TB. Relay 4EH is controlled by pole-changing contacts of relay 42TH and also by relays ZEF and 4 1 TR, and by a second reverse tralfic repeater relay 42EF.

Signalzi8L,is controlled similarly to signal All. by relays-8LH--and 8WH which are controlled for westbound traiiic movements similarly to the manner in which relays dRI-I and AEH are controlled for eastbound traffic movements.

Signal 4L is controlled by a home relay vJlLl-I and by a distant relay iLD. Relay 4LI-I may be controlled in part by lever 4V, as-showninFig. 1a. Relay 4LD may be controlled in any suitable manner by trafiic conditions west of signal 4L, and is shown controlled by a circuit-whichincludesr-a contact I99 of a track relay IMTR.

Signal 8B is controlled similarly to signal 4L by relays BRH and flRDiwhich may be controlled similarly to relays idLl-l', andrflLDrespectively.

Each of the signal levers has a normal posi- -tion-n, a reverse position fito the left, ;.as"shown in the drawings; for controlling westbound signals =and a reverse 'position'r to the right Efor controlling eastbound signals.

Signal-*4 l-Wv is 'controlled-byzrelay 4 1 TR: and by anorm-al traffic repeater relay 4 IWF. Signal 4213 is controlled similarly :to signal MW-by relay *42IR--and' by reverse traiific repeater relay AZEF.

A trafiic lever lVis provided in aninterlock- --ing machineior the interlocking layout .at'the west end-of the stretchof track X,and a second traiilic lever- 6V is provided inasecondinterlocking machine for the'interlockinglayout .at the east end'ofthe stretchof track X. Each of the "trafilc levers 'zvandfiv has a-normal position 11 and-areverse position 1" and also a normal lock position wand a'reverse lock position y.

Signal lever -8V is mechanically interlocked with traflic lever 6V in the interlocking machine "for-the eastend of the stretch of trackxwhich I shall refer to hereinafter as the east interlocking-machine,- so thatlever BV- must be in the normaLpositionn before lever-8V can be moved to its 'reverse position f for clearing signal 8L, and lever 6V-must-remain in its position-n while lever 8Vis in its position 1. Signal leverflV is me'chanically interlocked with traffic lever 2V in the interlocking machine for the west end of the stretch of track X, which I-shall refer to hereinafter as the westinterlocking machine, so that lever 2V must be in its 1* position before lever 4V can be --moved to itsreverse'position r for clearing signal 1R, andlever2V-must remain in its reverse posi- "HOT! 1 while lever 4V is in itsreverse position 1*.

Lever 2V is provided with an electric lock comprising a lock segment [3 which is mechanically operated by lever 2V=and a'lockmagnet 2K which controls-a lockingdog f4. When magnet 2K is -deenergize'd, locking dog l l :engages a projection l-on segment 13 if lever2V is moved-from its normal position-n to its-normal lock position a: -or-irom its reverse position r'to its reverse lock position y, thus preventingmovement of lever 2V .position or its 12 position or at any point between these .two positions, as indicated by reference character In adjacent contact 26.

An eastbound route locking relay 4E8 is controlled by lever 4V and by a normal trafiic repeater relay 2WF so that relay AES is deenergized whenlever 4V ismoved to its r position while relay ZWF is deenergized. A westbound route locking relay 8W8 for the interlocking at the opposite end of the stretch is controlled for westbound traffic movements similarly to the manner 'in-rwhichrrelay .4ES is controlled foreastbound tra'flic movements.

- A reverse stick relay v2RP,-of the slow release type, has 'a pick-up circuit controlled by a reverse contact of leVeriZV, and has a stick circuit controlledrbya back contact of a normal stick relay ZNP. Relay ZNP has a pick-up and a stick circuit, bo th of which are controlled by reverse tra'flic repeater relay ZEF, and the pick-up circuit is also controlled by a normal contact of lever 2V and by a front'contact of 'relaylRP. *A second normal stick relay ZNPShas a pick-up circuit controlled by a normal contact of a polar stick traffic relay 2F, and has a stick circuit controlled by a back'contact'of relay ZNP.

' A normal stick relay GNP, of the slow release type, for the'interlocking at the opposite end of the stretch, has a pick-up circuit controlled by a normal contact of lever 6V, and has a stick circuit controlled by a back contact of reverse stick relay 6R1. Relay 6RP has a pick-up and a stick circuit, both of which are controlled by a normal traffic repeater relay .BWF, and the pick-up circuit is also controlled by relay GNP and by a reverse contact of lever (W. A second reverse stick relay GRPS has a pick-up circuit controlled by a reverse contact of polar stick traffic relay 6F, and has a stick circuit controlled by a back contact of relay BRP.

Normal and reverse or westbound and eastbound traffic lamps 2w and 2e, respectively, are

controlled by me and ry contacts of lever 2V in the interlocking for the west end of stretch of track X. -'A block lamp 212 i controlled by block indication or trafic lever lock relay 2BR and by a reverse polar contact of relay 2F. In the interlocking at the east end of stretch of track X, westbound and eastbound traffic lamps 6w and 6e, respectively, are controlled by m: and Ty contacts, respectively, of lever 6V. Block lamp 6b 'iscontrolled by trafiic lever lock relay BBR-and by a'normal contact of polar stick traflic relay BE A westbound traflic control circuit is supplied,

at the east interlocking, with current from a source having terminals ZFB and 2FN, andincludes the traffic lever lock relays 2BR and BER and polar stick trailic relays 2F, 4I-42F and BF AL, .and the other of whichris also divided into sections such as sections 65 and 66 between signals 4L and 8E. The westbound traific control circuit also includes a jumper wire 92 acros the two control conductors atthe westinterlocking. The

"eastbound trafiic control circuit is similar to the westbound traiiic control circuit except that it is supplied with current from a source having terminals IFB and IFN, at the west interlocking, and include a jumper 83 across the control conductors at theeast interlocking.

Trailic relays 2F, 4l42F and SF are of the polar stick type each of which has two windings, such as windings 9 and H of relay 2F. When current passes from right to left in winding 9 and from left to right in winding II, as shown in the drawings, the forces exerted by these two windings on the contacts of the relay are additive, so that the contacts are moved to a correstick relay 2NPS, by traffic lever lock relay 2BR, and by polar stick trafiic relay 2F, and also by a latch contact operated in conjunction with lever 2V. Lock magnet 6K in the interlocking machine at the east end of the stretch of track X is controlled similarly to lock magnet 2K in the machine at the west end of the stretch, as just described.

Each of the polar stick traffic relays controls a slow release normal traific repeater relay and a slow release reverse trafiic repeater relay designated by the reference characters WP and EF, respectively with corresponding numerical prefixes.

Referring now to Figs. 2a and 2b, the track and .signal layout here shown is the same as in Figs.

1a and 1b.

The westbound traific control circuit, instead of being supplied with current at the east interlocking machine as in Figs. 1a and 1b, is here supplied with current of normal polarity from the source having terminals IFB and IFN at the west interlocking. The trafil-c control circuit here includes a code following relay 2CD instead of traffic lever lock relay 2BR for the west interlocking, and includes the back point of a contact of a code transmitting device 2CT.

In the form of apparatus shown in Figs. 2a and 2b, the normal and reverse stick relays employed in the form of apparatus shown in Figs. La and 1b are omitted.

In the westbound trafiic control apparatus, lock magnet 6K is controlled by a circuit which includes annr contact of lever 6V and a front contact of relay 6BR. Block lamp 6b is here nor- -mally lighted by a circuit which includes a front contact of relay 6BR.

In this form of apparatus, lever 6V, upon being moved to its 1' position, disconnects relay 6BR from the westbound traflic control circuit, and effects energization of a code transmitting device 6CT which periodically closes a path through a jumper 13'! across conductors H1 and I2!) of the westbound traffic control circuit. This causes relays 2CD, 2F, 4l42F and GP to be periodically respectively, of the traffic control circuits to prevent any flow of current due to difierence in potential of the two sources of current at the times the two sources oppose each other.

Since relay 2F, ll-42F and 6E are of the polar stick type, their contacts will not be moved during periodic energization of these relays by current of normal polarity following previous constant energization by current of normal polarity. Relay 2CD, however, being of the code following type, follows code transmitter SGT.

During the periods when the front point of the contact relay 2CD is closed, a decoding relay ZFSA is energized, and during the periods when the back point of the contact of relay 2CD is closed, a second decoding relay 2BSA is energized. A resistor is connected in multiple with the winding of each of the relays ZFSA and 2BSA in order to make these relays slow in releasing so as to retain their front contacts closed during the open periods in their control circuits while contact I25 of relay 2CD is being repeatedly operated.

A time element device ZTE is controlled by relay 2BSA, and a traffic lock stick relay 28 is controlled by time element device ZTE and by relay ZBSA. Traffic lever lock magnet 2K is controlled by front contacts of relays 2BSA and 2S, while lever 2V is in its normal position. Block lamp 2b is also controlled by relays 2S and 2BSA, and by relay 2BR.

The arrangement and operation of the eastbound trafiic control circuit is similar to that just described for the westbound traflic control circuit. The eastbound trailic control circuit is supplied with current from terminals 2FB and 2FN at the east interlocking and includes a second code following relay 6CD. A second code transmitting device 2CT is here controlled by an m: contact of lever 2V and by a contact of reverse trafiic repeater relay ZEF.

Referring next to Figs. 3a and 3b, the track and signal layout here shown is also the same as in Figs. 1a. and 1b except that here a track switch Z is shown at an intermediate point in the stretch of track. Switch Z is provided with an electric switch lock having a lock magnet WL, and the traffic control circuits of Figs. 1a and 1b are here modified for controlling the electric switch lock for switch Z. A switch lock control lever IGLV is provided in the west interlocking machine, and a switch lock control lever I2LV is provided in the east interlocking machine, for controlling the electric lock for switch Z. Each of the switch lock control levers is interlocked with the signal lever for governing traflic movements onto its end of the stretch X so that, when either of the switch lock control levers is reversed the signal lever controlling the signal for governing traffic movements onto the corresponding end of the stretch cannot be reversed.

The westbound traffic control circuit is here modified to include a resistor I 62 and front points of contacts LP-l63, LP-I64, LP-IBS and LP-IBG of a switch repeater relay LP. The eastbound traffic control circuit is similarly modified to include a resistor I68 and the contacts of repeate relay LP.

A lock bar I'll is rigidly secured to switch Z for engagement with a dog ill) by means of which the switch may be locked in its normal position,

in which fit is shown in Fig. 3a of the drawings.

Dog H0 is actuated by means of a manually operable switch lever which is designated by the reference character Ill-IZV, and which has normal :and :reverse positions designated :by the :neference -charac.t ers n andrf. r iv ly- Movement oflever Ill-UV iscontrolledby lock zmagnet WL which .has an armature provided witha dog I13 for engagement withnotches in i a lock segment 112. The :armature of magnet WL also operates-aback contact H6. Segment 1.12gisrigidlyconnected with lever Ill-12V, and .is :therefore operated by lever l-|2V.

A contact Ill, operated in conjunction with .switch .2, is normally closed, but becomes opened :whenswitch Z is reversed.

:Gontacts H and 489 associated with .the switch'lockmay be operated in any suitable man- .ner -suchyfor example, as by the bow 114 of a padlock-P for-switch lock lever Ill-12V. When i'l adlockPiis removed from the switch lock lever, contact H5 becomes opened-and contact I80 be- :comes closed.

-.When contact H5, operated by how -I M of padlock 'P, becomes opened, :switch repeater relay LP becomes deenergized, and its contacts .LP-lj63, LP-164, LP-"i65 and LP-IBB in the -traflic control circuits become opened "at their front points, and become closed at their back points for-connecting a high resistance switch lock control relay IULR with conductors 5'3 and '65 of the west endof the traffic control circuits and for connecting a second high resistance switch lock control relay IZLR with the east end ofthe trafiic control circuits.

If the westbound trafiic control circuits has previously been closed,-acircuit will now be closed -which includes-resistor I62 and the winding 'of 'relay *HLR. The apparatus is so proportioned that, when resistor H32 is connected in series Withhigh-resistiince relay l-ZLR, the front contacts ofrelays BER and IZLR. will be open. If switch lock control lever 12LV isnow moved to its reverse position r, a circuit for trafiic lever lock magnet fiKwill be opened at a contact of lower IZLV, and resistor 462 will be by-passed :by'a reverse contact of lever l 2LV,-so that relay IZLR will now -be energized sufficiently to close "its 'front contacts for effecting energization oi switch lock magnet WL.

Switch lock magnet WL may also be similarly controlled manually, by the switch-lock control lever llILV tin the west interlocking .machine, throughhigh resistance switch lock-controlrelay 'IIJLR, or it may be controlled automatically through-a time element device LTER, which may, -for example, be a time element relay .which is in turn controlled by a back contact-of relay 4ITTR.

Referrin finally to Figs.4a and 4b, the form of apparatus shown in Figs. 3a and 3b is here modified to include a normal contact of one of "the switch lock control levers in each ,of the trains control circuits instead of including a resistor I62 or (68, and to control a code transmittingdevice byra reverse'contact of each of the "switch lock control levers. Code transmitter ECT is shown thus controlled by'lever IZLV. vA code'repeating relay ECTP is in turn controlled by code transmitter ECT as well as by lever WIN. .A slow pick-up relay ECTPP is controlled by a back contact of relay ECTP, so that-when relay ECTP is being repeatedly energized and deenergized, the 'front contacts of :relay ,ECTPP willbe open.

Switch lock control relays IOLR-andLZL-R are here of the code following'type, :and :are connected through condensers 186 :with the -:back points of the contacts of relay LP. Ir leverlZLV *is moved :to its rposition when relayLRisdeenergized while the westbound traific control circuit is :set up, relay IVZLR will be energized :by

coded current for-energizing slow releasing-decoding relays FSA and BSA. Relay IOLR may be similarly controlled by lever IiJLV for :controlling relays FSA and BSA. Electric switch lock magnet WL is controlled by relay BSA.

Having described, in general, the arrangement and control of the apparatus shown :byitheaccompanying drawings, I shall now describe, in detail, its operation.

As shown by the drawings, all parts are in the normal condition, that is, the normal or westbound .traffic control circuits are arranged for westbound trailic movements; all signals except signal MW are indicating stop; .Signal MW is indicating caution; relays 4LH:and, 8RH are deenergized, and hence relays TR and 42TH, respectively, are energized by current of reverse polarity; thesignal levers, traific levers and-switch lock control levers are in their normal or n positions; electric locks for the trafiic levers are deenergized; the polar stick trafiic relays are energized by current of normal polarity; relay BWH is energized by current of normal polarity; route locking relays 4ES and 8W3, first normal stick rela GNP, second normal stick relayiNPS, second reverse stick relay BRPS, normal tra'flic repeater relays ZWF, MWF and 6WF, distant signal relays 4LD and 8RD, and traffic'lever lock relays 2BR and 6BR in Figs. 1a, 1b, 3a, 3b 4aand 4b are energized; relays 2CD, 2FSA and 6BR in Figs. 2a and 2b are energized; relays LP in Figs. 3a, 3b, 4a and 4bare energized; relay ECTPP in Fig. 4b is energized; relays 4LH, dRH, 4EH, 8RH, SLH, first reverse stick relays 2RP and BRP, first normal stick relay ZNP, and reverse traffic repeater relays ZEF, 42EF and BEF are deenergized; relays ZBSA, BBSA, BFSA, 2S and 6S, and code transmitters 201 and BCT in Figs. 2a and 2b are deenergized; relays IOLR, IZLR and LTER, and switch lock magnet WL in Figs. 3a and 4a are deenergized; relays FSA. BSA and EC'I'P, and code transmitter ECT in Figs. 4a and 4b are "deenergized; normal or westbound traflic lamps 2w and 6w and block lamp 6b are lighted; and reverse or eastbound traffic lamps 2e and 6e and block lamp 2b are unlighted.

In Figs. 1a and lb the circuit by which relay 4ITR is energized by current of reverse polarity passes from-the positive terminal of abattery 5, through the back point of contact 18 of relay ILH, one of the rails of section b-c, winding of relay TR, the other rail of section b-ccontact ATR-l'l, and back point of contact 16 of relay ALI-I back to battery 5. Relay 42TH is energized by a similar circuit.

Lamp R of signal 4R is lighted by a circuit passing from terminal EB of a suitable source of lighting current, through the back point of contact l9 of relay v4RH,and lam R of signal 4R to terminal EN of the same source of .cur-

:4IW is lighted by a circuit passingfromterminal EB, through the front point ofcontact 23 otrelay MWF, 'front point or contact 24 of relay UTE, contact 25 of relay MTR-closeddnthe reverse position, and lamp Y of signal 4|W- to terminal EN.

Two pick-up circuits for relay 4ES are closed, one of which passes from terminal B of a suitable source of current, through contact 26 of lever 4V, and the other of which passes from terminal B, through contact ZWF-Z'l, and both of which then pass through contact 28 of relay lTR, and the winding of relay 4E8 to terminal N of the same source of current. Two stick circuits for relay 4ES are also closed which are the same as the pick-up circuits just traced except that they include contact 29 of relay 4ES instead of contact 28 of relay ATR.

One of the pick-up circuits for. relay BWS is closed, passing from terminal B, through contact 26 of lever 8V, contact 28 of relay GTR, and winding of relay 8WS'to terminal N. One of the stick circuits for relay BWS is also closed, and is the same as the pick-up circuit just traced except that it includes contact 29 of relay BWS instead of contact 28 of relay BTR.

The pick-up circuit for relay ZNPS is closed, passing from terminal B, through contact 3|] of relay 2F, and the winding of relay ZNPS to terminal N. A stick circuit is also closed for relay ZNPS, passing from terminal B, through contact 3| of relay 2NP, contact 32 of relay ZNPS, and the winding of relay ZNPS to terminal N.

Both a pick-up and a stick circuit for relay GNP are closed, the pick-up circuit passin from terminal B, through contact 33 of lever 6V, and the winding of relay GNP to terminal N. The stick circuit for relay GNP passes from terminal B, through contact 34 of relay GRP, contact 35 of relay GNP, and the winding of relay GNP to terminal N. I

Relay GRPS is energized by a stick circuit, passing from terminal B, through contact 31 of relay GRP, contact 38 of relay GRPS, and the winding of relay GRPS to terminal N.

Relay 8WH is energized bycurrent of normal polarity in a circuit passing from terminal B,

through the front point of contact 39 of relay.

MTR, contact 40 of relay MWF, contact 4| of relay 42TR, contact GWF-AZ, winding of relay 8WH, and the front point of contact 43 of relay MTR, to terminal N.

Relay BBB is energized by its circuit which includes contact I98 of relay 08TR, Relay 4LD is energized by its circuit which includes contact Block lamp 6b is also lighted by a circuit passpoint of contact 6WF-49, back. point of contact 50 of relay GRP, contact BWS-Bl winding of relay 6BR, upper winding of relay GF, contact 8WH-52,

conductor 54, contact 55 of relay 42TH, upper winding ofrelay- 4l-42F, contact 56 of relay TR, conductor 51, contact ZWF-58, upper winding 9 of relay 2F, winding of relay 2BR, contact IES-GO, back point of contact 6| of relay 2NP, back point of contact 2EF-62, jumper wire 92, front point of contact 2WF-G3, back point of contact 64 of relay ZNP, lower winding ll of relay 2F, conductor 65, lower winding of relay 4l42F, conductor 65, lower winding of relay 6F, back point of contact 61 of relay GRP, and the back point of contact GE-F-GG to terminal ZFN.

With relay 6F energized by current of normal polarity, normal or westbound traiiic repeater relay GWF is energized by a circuit passing from terminal B, through contact 69 of relay GP in its normal or left-hand position, contact 10 of relay GEF, and the winding of relay GWF to terminal N. Relays ZWF and 4|WF are also energized by similar circuits.

I shall assume that, with traflic controlling apparatus of the form shown in Figs. l a and lb, a train is to move in the westbound direction over stretch of track X. With lever 6V in its normal position, the mechanical interlocking between levers GV and 8V permits lever 8V to be moved to its f position for clearing signal 8L.

Lever 8V, upon being moved to its 1 position, opens its contact 26, thereby deenergizing westbound route locking relay BWS. With relay 8WS deenergized, contact 8WS-5l opens the westbound traific control circuit, thereby deenergizing traflic lever lock relays 2BR and BER and traffic relays 2F, 4l42F and 6F.

Since relays 2F, 4l-42F and SF are of the polar stick type, their polar contacts will remain closed in the normal position after these relays become deenergized. When relay 6BR becomes deenergized, its contact 46 opens the circuit for block lamp 6b which is thereby extinguished. Contact 16 of relay 6BR in the circuit for lock magnet 6K is also now open. Block lamp 61), on account of being extinguished, indicates to the leverman that lock magnet GK cannot now be energized by closing latch contact 18 of lever 6V.

Lever 8V, upon being moved to its f position, closes a circuit for energizing relay 8LH, this circuit passing from terminal B, through contact 12- of relay 8TB, contact 6WF-l3, contact 14 of lever 8V closed. in the 1 position, and the winding of relay BLH to terminal N. With relay llLI-I energized, green lamp G of signal 8L becomes lighted .by its circuit passing from terminal EB, through the front point of contact H! of relay 8LH, front point of contact 8WH-20, contact 8WH-2| closed in the normal or left-hand position, and lamp G of signal 8L to terminal EN. 7

If, now, a westbound train passes signal 8L, deenergizing relay GTR, relay BLH will become deenergized by the opening of contact 12 of relay BTR. With relay BLH thus deenergized, red lamp R of signal 8L is again lighted by its circuit previously described. With relay 8TR deenergized, its contact 28 is open in the pick-up circuits for relay 8W8, and therefore relay BWS cannot again become energized until the train has vacated section. d-e.

The train, upon entering section cd, deenergizes relay 42TH. which then permits its contact 4| to open the circuit for relay 8WH. With relay 42TR deenergized, contact 55 opens the westbound trafiic control circuit at another point, this circuit having been previously opened at contact 8WS5 I. When relay 8WH becomes deenergized, this relay, at its contact 8WH-52, opens the westbound traffic control circuit at a third point. Relay 6BR therefore remains deenergized while the train is progressing in the westbound direction over the stretch of track X.

assesse When the trainleaves sectiond-e, relay-8WSi= can again become energized by its pick-up circuit previously traced, as soon as the leverman restores lever 8V to its n position.

When the train enters section b-c, deenergizing relay MTR, contact 24- of relay MTR opens, at its front point, the circuit for lamp Y of signal MW, thereby extinguishing lamp Y, and contact 24 then closes, at its back point a circuit'for lamp R of signal 4 IW, this-circuit passing from terminal EB through the front point of contact 23 of relay MWF, back point of contact 24 of relay TR, and lamp R of signal 41W to terminal EN. When relay MTR becomes deenergized, its contact SGopens the westbound traffic controlcircuit at a fourth point.

If the levermanat the west interlocking moves lever 4V to its 1 position, thereby energizing relay 4LH by its circuit, which includes contact 200 of lever 4V and contact 20! of relay 4TB, while relay 4LD is energizerd, lamp G of signal 4L will be lighted by its circuit passin from terminal EB, through the front point of contact ill of relay 4LH, front point of contact 22 f relay'dLD, and lamp G of signal 4L to terminal EN. When the westbound train now enters section a-b, deenergizing relay 4TB, relay lLI-l will again become deenergized, causing lamp G to be extinguished and lamp R. of this signal to again be lighted by its circuit previously described.

When relay 4TB becomes deenergized, contact 28 opens the pick-up circuits for relay 4E8, but this relay remains energized by its stick circuits previously described.

If the leverman at the east interlocking has returned lever 8V to its Tlposition, relay BWS will be energized and contact 8WS-5I will therefore be closed inthe westbound trailic control circuit.

When the train leaves section cd, relay SWI-I becomesenergized by current of reverse polarity in a circuit which is the same asthe circuit previously traced for this relay except that it includes the back points instead of the front points of contract 39' and 43 of relay l-ITR'. Contact 8WH-5Z is therefore also again-closed in the westbound trafiic control circuit, and with relay 42TR energized, contact-55 0f this relay is also closed in the westbound trafiic control circuit.

When the train now leaves section 12-0 permitting relayv MTR to again become energized, contact 56 of thisrelay completes the westbound trafliic controlrcircuit, .so that traific 1everlock-re-' lay 6BR again becomes energized; and block lamp 6b again becomes lighted, by its.-circuit previously traced, and indicates to the leverman at the east interlocking that the block is clear and that lever 6V can now be moved-to its r position if desired.

It follows that from the time the levermanat the east interlocking moves lever 8V. to its f'position for clearing signal 8L until the westbound train leaves section 22-0 and lever 8V is restored to its 12 position, the westbound trafllccontrol circuit is open causin relay 6BR to be deenergized and block lamp-6b tobe-extinguished; and preventing lock magnet 6K from being energized by closing latch contact 78 of lever (W.

I shall now assume that, after the Westbound train has left section 11-?) and all parts of the apparatus are again in their normal condition, it is desired to arrange for a traflic movement in the reverse or eastbound direction. The leverman at the east interlocking will therefore close latch contact 18 of lever 6V preparatory to moving lever 8V to'its'r position. Lock magnet 6K will nowbe energized by itscircuit passing'from terminal 1- 2 B, through contact 15 of-*reIay GRRS; contact-l5 of relay 6BR, contact ll of relay 6F, the winding of lock magnetGK, and latch contactm tmterminal N. Lock magnet-GK, upon becoming ener-- gized, lifts its-dog ll out'of enga gement with pore tion l5-of lock segment l3; so that the':leverrnan= can" now move lever fiv toits 1 position;

When leverlW is moved todts r'po'sifion', its: contact 33' opens the pick-up circuit for. relay GNP, but-this relay rema'ins:energizedaby its stick circuit previously traced. Also, contact 5'41 of lever (W opens the circuitrfor: westbound;trafficv lamp 610, thereby extinguishing-this'lamp; When: lever 6V reaches itsreverse lock:.position.y,.its: contact.45' closesza circuit for: lighting reverse or eastbound tiafilc; lamp: 6e; this: circuitv passing; from terminalfEB. throughcontact 4520i lever. 6V, and lamp 6e,.to1 terminal ENC When lever GV- reachesits:rposition; a pick-up circuitiis closed ior:energizingrelay BRP, this'circuit passing from terminal'B; through; contact BW'F-lfl, contact 80.: of relay GNP, contact: 81 of" lever: 6V, and the winding of relay GRPtO terminal N..

Relay (SRP;v upon. becoming: energized by its pick-up circuit, completes its stick circuit passing-- from terminal; B, through: contact 6WF-l9:,,con tact. 8250f relay ERR; and,the winding ofv relay.- GRP to terminal Na Relay 6RP,-.up.on becoming energized, opens: itsco'ntact 31 in the: StiCk ClI:-" cuit for: relay 6EPS, causingv relay; GRPS tobe deenergized. Relay BR-PS? will. remain deener-- gized untilrelay: 6F closes its contact 36? in' the reverse position;

With relay; BRPS: deenergized; its: contact 15 is open. in the circuit for; lock. magnet 6K, and therefore lever ltV cannot be: returned to its. 1: position immediately after being moved; tozits; 1" position.

Relay ERR, upon becoming energized, also opens its contact 34*in'athe:stick circuit for relay GNP, thereby deenergizingmelay GNR. RelaySNP; on account of beingofJthe-slow releasing type, retains :its'front: contactsclosectforv a brief period of time after itsstick circuitis opened.

With relay BR-P energized,,relays 6F, fl-AZF and. 2F become energized by current of. reverse. polarity passing fromnterminal. 2E!B,.through the front point of contact 61 of relay' 6R1, lower winding of relay- 6F, conductor 66, lower. winding of relay 4l-4'2F, conductor.-' 65, lower, Winding ll. of relay 2E, backipoint; of contact Miofrelay-ZNP, front point of contact 2WF-63, jumper 92', back point'of contact' 2EF-'-62-; back point of contact 61 of' relay ZNP, contactAES-fil); winding of relay 2BR, upper winding 9' of relay 2B, contact ZWF-BB, conductor 57-; contact 560i relay 41TH, upper'winding of rel'ay H I'ZF; contact 55 of relay 42TR, conductor 5% contact-BWH-SZ, upper winding-of relay 6F, winding of relayfiBR; contact 8WS-'5|", and the front point ofcontact 58 of relay BRP to terminal ZFNL The polar stick traffic relays, upon becoming energized by current of reverse polaritywill move their polar contacts. to the reverse or right-hand position as shown in the drawings.

Contact. Ii-of relay BB is therefore nowopened in the-circuitfor lock magnet 6K. Contact 41 of relay- 61 is'also opened, causing block lamp 6b tobe;extinguished.. With contact 69 of relay 6F alsoopen inits: normal position,.relay GWF will be deenergized. Relays 2WE and MWF are similarly deenergized with contact 36' of relay- 6F closed; relay SRPSwill' become energized by" its pick-up circuil'; passing-from terminal B; through 13 contact 36 oi relay BF, and the winding of relay SRPS to terminal N.

With contact 69 of relay SF in its reverse or right-hand position, as shown in the drawing, reverse or westbound traffic repeater relay 6E? will be energized by a circuit passing from terminal B, through contact 69 closed in the reverse position, contact II of relay GWF, and the winding of relay BEF to terminal N. It will be noted that relay SWF is of the slow releasing type, so that its contact II will not become closed until after contact 69 of relay 6F has become closed in its reverse position. Relays 2EF and 42EF will also be energized by circuits which are similar to the circuit just traced for relay GEF. When relay 6WF becomes deenergized, its contact BWF-IS opens the pick-up and stick circuits for relay BRP, causing relay BRP to become deenergized.

With relays BRP and BWF deenergized, and with relay BEF energized, the east end of the eastbound trafic control circuit is now completed through a jumper 83.

When relay BWF becomes deenergized, its contact 6WF-42 opens the circuit previously traced for relay BWI-I, causing this relay to become deenergized. With relay BWH deenergized, its contact 8WH-52 is now open in the traffic control circuit, but contact BEE-53 is now closed around contact 8WH-52.

With relays 2EF and 42EF energized, relay 4EI-I becomes energized by current of normal polarity passing from terminal B, through the front point of contact 84 of relay 42TR, contact 85 of relay 42EF, contact 86 of relay 4ITR, contact ZEF-Sl, the Winding of relay 4EH, and front point of contact 88 of relay 42TR to terminal N.

With relay 2WF now deenergized, its contact 2WF58 is open in the trafiic control circuit, but with relay 4EH now energized, contact 4EH-59 is closed around contact 2WF-58.

With relay 6WF deenergized, its contact BWF- 13 is now open in the circuit previously traced for relay 8LI-I.

With relay GEF energized, a second pick-up circuit is closed for relay 8WS which is the same as the pick-up circuit previously traced for this relay except that it includes contact 6EF-2'I instead of contact 26 of lever 8V.

With relay 4 IWF now deenergized, yellow lamp Y of signal M W is extinguished, and red lamp R of this signal is now lighted by a circuit similar to the circuit previously described for red lamp R of signal 42E. With relay 42EF energized, red lamp R of signal 42E is extinguished, and yellow lamp Y of this signal is lighted by a circuit which is similar to the circuit previously traced for yellow lamp Y of signal 4IW.

With relay 2F energized by current of reverse polarity, the pick-up circuit for relay ZNPS is open at contact 30 of relay 2F. Relay ZNPS, however, is still energized by its stick circuit previously traced.

With the contacts of relay 2F closed in their reverse position, block lamp 2b is now lighted by a circuit passing from terminal EB, through contact 46 of relay 2BR, contact 48 of relay 2F, and block lamp 2b to terminal EN. The lighting of block lamp 2b indicates to the leverman at the west interlocking plant that lever 2V can now be moved to its reverse position r.

With relay 2EF energized and relay 2WF deenergized, the portion of the westbound traific control circuit which includes jumper 92 is now open at the back point of contact 2EF-62 and at the front point of contact 2WF-63., i

The eastbound traffic control circuit is therefore now completed for energizing the polar stick traffic relays by current of reverse polarity, this circuit passing from terminal IFB, through the front point of contact 2EF-62, back point of contact 6| of relay 2NP, contact 4ES-6U, winding of relay 2BR, upper winding-i=9 of relay 2F, contact 4EH59, conductor 51, c0ntact 56 of relay 4ITR, upper winding of relay 4I-42F, contact 55 of relay 42TR, conductor 54, contact BEE-53, upper winding of relay 6F, winding of relay 6BR, contact BWS-5I, back point of contact 50 of relay BRP, back point of contact 6WF-49, jumper 83, front point of contact 6EF-68, back point of contact 61 of relay BRP, lower winding of relay 6F, conductor 66, lower winding of relay 4I42F, conductor 65, lower winding II of relay 2F, back point of contact 64 of relay 2NP, and the back point of contact 2WF-63 to terminal IFN.

The leverman at the west interlocking plant will now manipulate lever 2V for closing its latch contact 18, thereby completing the circuit for energizing lock magnet 2K, this circuit passing from terminal B, through contact 89 of relay 2NPS, contact 90 of relay 2BR, contact SI of relay 2F, winding of magnet 2K, and latch contact I8 of lever 2V to terminal N. Lever 2V, upon being moved to its 1' position, opens its contact in the pick-up circuit for relay 2NP, and opens its contact 44 in the circuit for lamp 2w, thereby extinguishing lamp 2w.

Lever 2V, upon reaching its reverse lock position, completes a circuit for energizing trafiic.

lamp 2e, this circuit passing from terminal EB,

through contact 45 of lever 2V, and lamp 2e to terminal EN.

When lever 2V reaches its 1 position, relay mits lever 4V to now be moved to its 1' position for clearing signal 4R for an eastbound traffic movement. With lever 4V in its 1' position, relay ,4RH becomes energized by its circuit passing from terminal B, through contact IOII'of relay 4TR, contact 2EF-IOI, contact I02 of lever 4V,' and the winding of relay 4RH to terminal N.,.

In Figs. 2a and 2b, normal or westbound trafiic.

lamps 2w and 6w are lighted as in Figs. 1a and lb. Block lamp 6b is here lighted by a circuit passing from terminal EB, through only contact BBR-I 03 and lamp 6b to terminal EN.

The westbound traffic control circuit is here energized from the west interlocking instead of from the east interlocking as in Figs. 1a and lb.

The westbound traffic control circuit which is closed in Figs. 2a and 2b passes from terminal IFB, through asymmetricunit Ii, contact I04 I I0, contact II I of relay 4ITR, upper winding of relay 4I42F, contact II2 of relay 42TR, conductor II 3, contact 8WHI I4, upper winding of relay 6F, contact 8WS-I I6, conductor 1, con- 15 tactJ IE' of lever 6V winding ofirelay 6BR; contact N9 of lever-6V; conductor I29; lower winding of relay 6F; conductor I2 4 lower winding of relay M--42F conductor I22; lowenw-inding of relay 2F,- conductor I23 andcontact ti t-of lever 2Vto terminal I FN.

With relay 2CD constantly energized,- decod ingrel'ay 2FSA- is constantly energized-by its cir cuitthroughthe none point of contact I-25 ci relay 2CD, and therefore its contactl lil-isclosed; but'since contact I25-of relay 2CD remains open atits back point relay 2135A does not-become energized.

l shall assume that; with the form of apparatus showniii-Figs; 2a and 225, an eastbound trams movement is to be made. Withlamp (3b lighted,

the leverman in the east interlocking knows that the blockisun'occupied and th'at lever 6V canbe moved to its r position; He, therefore; closes latch contact 18 of lever 6V, thus completing a circuit for energizing lock magnet 6K, this circuitpassing fromterminal B, through the back point of contact SS-I26, contact STE-I21; cn tact GER-I28, contact I29 of lever 6V, lock magnet GK, and latch contact T8 of lever SV'toterminal-N; Magnet 6K, upon'becoming energized,

lift'sits dog I4-outof engagement with projection I of'lock segment [3, and the leverman then moves lever 6V to its 1* position.

Lever- 6V, upon being moved away from its normal lock position, opens its contact I29 in the normal lock circuit just traced for magnet GK, and opens its contact l l'inthe'circuit previouslydescribed for Westbound traffic lamp 8w, causing lamp 6w to be extinguished. Also, when lever 6V is moved from its normal lock position as, its contacts H8 and H9 open the circuit for relay 6BR, causing relay 6BR to become deenergized;

Lever 6V; upon reaching its reverse lock position 3 closes itscontact I59 in-the reverse lock circuit for magnet 6K, and closes itscontact 45 in a circuit passing from terminal EB, through contact'45 of lever 6V and lamp 66 to terminal EN for lightingeastbound trafiic lamp 66. When lever 6V reaches lts'y position, acircuit is completed for energizing code transmitter'fiCT, this circuit passing, from terminal B, through contact I30 of lever 6V, contact GWF-I3I, andthe Wind"- ing of'code transmitter GCT to terminal N. At

the same time, the east end of the eastbound traflic control circuit is connected through contacts I32 and I33 of lever 6V with terminals 2FB and ZFN, respectively;

With code transmitter SCT energized, its contact I34 repeatedly closing alternately at its front'and'back points. During thevperiodswhen contact I34 of code transmitter 6CT is closedat' it front point, a path is completed from conductor II'I, through the front point'of contact I34 of code transmitterGCT, jumper I31, and contact 6WF-I33, to conductor 120. Duringthe periods when contact I34 of code transmitter 60'1" is'closed at its front point, code following relay ZCD'is energized by a circuit which is the same as the westbound trainc control circuit previously traced except thatlit includes the pathjust described from conductor II! to conductor I20 through jumper I31 instead of the path through the winding of relay 6BR.

When contact I34 of code transmitter ECT is closed at its back point, current ceases to flow through relay 2CD because at that time the source of" current at the west interlocking is opposedby the' source of current'at the east interlocking- Relay 2CD; therefore; is periodicallyenergized following code transmitting device HGT. With relay Z CD- following code transmitter BCT, relay ZFSA- is periodically energized by itscircuit passing from terminal B; through the front point of contact= l2 5 of relay 2CD, andthc winding- 0f relay ZFSA in multiple with aresistor of contact IZS-of relay 2CD; and the front-point of contact IMlof relay ZFSA and the winding oi relay Z-BSA in multiple with: a resistor l l l toterminal N:

With-relay 288A energized, time-element device*2IE- becomes-energized by its circuit passing: from terminal B; through contact 5-2 I of relay- 2BSA, contact MS of relay 2S, and the control 1 element'of deviceZTE to terminal N.

Time element deviceZTE, uponthe-lapse of a measured period of time, closes its contact I44; thereby completinga pick-up-circuit forrelay 2S, passingirom-terminal B; through contact I44 of timeelement device 2TB, and the winding of relay 2S to-terminal N. Relay 28, upon becoming energized by its pick-up circuit, completes itsown sticlr circuit passing fromterminal B;

through contact of relay ZBSA, contact I45- of relay 2S, and the winding of re1ay 2S tater-- minal N. Relay 25, upon becoming energized, opens the circuit traced for timeelement device 2TB; causing time elementdevice 2'TE to become deenergized.

With relays 2S and 238A energized, a circuit is completedior lighting block lamp 2b; this circuit passingfromterminal EB, through contact 28-! 50,- contact 2BSAI 5| and lamp 227 to terminal EN. The lighting of lamp 2b-indicates to the 'leverman in the west interlocking plant that he can now reverse-lever 2V, and that the blockis unoccupied'. He,- therefore, manipulates lever 2V for closing its latch contact 18, thereby completing a circuit for energizingmagnet thi's-circuit passingfrom terminal B, through the front point of contact 2844-1, cQntactQBSA-MG; con-- tact 549 of lever 2V, winding of' magnet 2K, and latch contact I8 of lever 2V to terminallN.

Lever 2V, upon being moved away fromitsnormal lock position :6, opens-the circuit just traced for energizing magnet 2K, and also the circuit for traffic lamp 211;, causing this lamp to b-eextin-- guished. At the'same time, the sourceof energy for thewestboundtrafiic control circuit is disconnected at contacts I04 and Ifldof'lever 2Vl Relay 2CD therefore becomes deenergized, causing relay ZFSA to be deenergized, which causes relays 238A and 28 in succession to also be deenergized.

When lever 2V reaches its reverse lock position v, its contact I57 becomes closed in a second circuit for magnet 2K, and itscontactAS becomes closediin a circuit for lightmgieastboundtraihc' lamp 2e. At the same time relay 2BR- is. connect-= ed through contacts 53: and I 54' of lever. 2V across conductors IiiBand I 23-at the westencl of the eastbound trafiic control circuit.-

Relays 2BR, 2F, ll-42F, and SF are therefore energized by current of reverse polarity, during the intervals when contact. I34.of code transmitter GUI is closed at its back point inthe east.- bound trafiic control circuit passingirom terminal EFB, through asymmetric unit 22', contact I32 of lever 6V, winding of relay 6CD, back point of contact I 34 of code transmitter GOT, conductor I I1, contact 8WSI I6, upper winding ofrelay 6F;

17 contact 8WH-I I 4, conductor II3, contact N2 of relay 42TH, upper winding of relay Ill-42F, contact III of relay 4ITR, conductor IIILcontact 2WF-II18, upper winding of relay 2F, contact 4ES-I91, conductor I96, contact I53 of lever 2V,

winding of relay 2BR, contact I54 of lever 2V, conductor I23, lower winding of relay 2F, conductor I22, lower winding of relay kl-42F, conductor I2I, lower winding of relay 6F, conductor I20, and contact I33 of lever 6V, to terminal ZFN.

Relays 2F, 4I-42F and BF, upon thus being energized by current of reverse polarity, move their polar contacts to the reverse position, thereby deenergizing normal traffic repeater relays 2WF, BWF and IIWF, and energizing reverse traflic repeater relays ZEF, BEF- and 42EF. With relay BWF deenergized, code transmitter IiCT becomes deenergized, so that its contact I34 remains constantly closed at its back point.

Contact ZWF-IGB in the trafiic control circuit is now open, but contact IEH-IIJQ is closed around this contact, as previously described for contacts 2WF-58 and 4EH-59 in Figs. 1a and 11). Similarly, contact SWH-I Id in the traffic control circuit is now open, but contact GEF-I I is closed around this contact.

With relay 2BR energized, block lamp 2b is now energized by a circuit passing from terminal EB, through contact 2BR.-I52, and lamp 2b to terminal EN.

In Figs. 3a, and 3b, a normal or westbound traffic control circuit is closed, and includes the parts of the normal traffic control circuit traced in Figs. la and 1b, and in addition to the normal traffic control circuit of Figs. 1a and 1b, the normal trafic control circuit of Figs. 3a and 3b includes a resistor I62 and front points of contacts LP-I63, LP-I64, LP-I65 and LP-I66. The castbound trafiic control circuit in Figs. 3a and 3b differs similarly from the eastbound trafiic control circuit of Figs. 1a and 122 by including a resistor I68 and the front points of the contacts of relay LP.

The circuit by which switch repeater relay LP is energized passes from terminal B, through contact I15 operated by bow I14 of padlock P, contact I16 of switch lock magnet WL, contact I11 operated in conjunction with switch Z, contact I18 of time element device LTER, and the winding of relay LP to terminal N.

I shall assume that, with apparatus of the form shown in Figs. 3a and 3b, and with the normal or westbound traffic control circuit closed as shown, a train is to move off of siding D onto track X over switch Z in its reverse position. A trainman will remove bow I14 of padlock P from the electric switch lock for switch Z, thereby opening contact I15 and closing contact I80, both of which are operated by bow I14 of padlock P.

With contact I15 thus opened, relay LP becomes deenergized, and completes a circuit passing from terminal ZFB, through resistor I62, front point of contact 6WF-49, back point of contact of relay GRP, contact 8WS-5I, winding of relay 6BR, upper winding of relay 6F, contact 8WH-52, conductor 54, contact of relay 42TR, upper winding of relay II42F, contact 56 of relay 4ITR, back point of contact LP- I63, winding of relay IZLR, back point of contact LP-I65, lower winding of relay l I42F, conductor 66,1ower winding" of relay 6F, back point of contact 61 of relay GRP, and the back point of contact BEE-68 to terminal ZFN.

18 The apparatus is so proportioned that, with resistor I62 in series with the high resistance of relay I ZLR, relay 6BR will release its front contacts and relay I 2LR will not pick up its front contacts.

With relay 6BR thus deenergized, block lamp 612 will be extinguished.

both be sufficiently energized to close their front The leverman in the east interlocking will therefore now reverse lever I2LV, thereby closing contact I61 for by-passing resistor I62. With resistor I62 by-passed, relays IZLR and 6BR will contacts, by a circuit which is the same as the circuit previously traced for relay IZLR, except that it includes contact I61 of lever I2LV instead of resistor I62. With relay I2LR thus energized, a circuit will be completed for energizing switch lock magnet WL, this circuit passing from terminal B, through contact I19 of relay I2LR, contact I operated by padlock P, and lock magnet WL to terminal N.

With switch lock magnet WL thus energized, it will lift dog I13 out of engagement with lock segment I12, thereby permitting lever Ill-42V to be moved to its r position for unlocking switch Z by removing dog I10 from engagement with lock rod Through the mechanical interlocking of levers 6V, 8V and I2LV, lever 8V will be locked in its n position by movement of lever I 2LV to its 1 posi-' tion while lever 6V is in its n position.

I shall next assume that the stretch of track X, as shown, is again unoccupied, and that the normal traflic control circuit is again closed for a westbound traific movement. I shall assume further that the leverman in the east interlocking clears signal 8L, and that a westbound train proceeds over track X through sections de and cd and then stops on section b'c in advance of switch Z to enter siding D, and that a trainman then removes padlock P from the electric switch lock for switch Z.

With relay IITR deenergized by the train on section bc, time element relay LTER will be energized by a circuit passing from terminal B, through contact IITR.I8I, and the winding of relay LTER to terminal N. Upon the lapse of a measured period of time, relay LTER will close its front contact I 82, thereby completing a circuit for energizing switch lock magnet WL, this circuit passing from terminal B, through contact I82 of relay LTER, contact I80 operat d by bow I14 of padlock P when the trainman removes padlock P from the switch lock, and the winding of switch lock magnet WL to terminal N, thereby permitting lever I Il-I 2V to be reversed for unlocking switch Z.

I shall next assume that the stretch of track X is again unoccupied, and that the apparatusis again in its normal condition with the westbound trafiic control circuit closed. I shall assume further that the leverman then reverses lever 6V for closing the reverse or eastbound trafiic control circuit. At the time the leverman closes latch contact 18 for energizing magnet 6K, the circuit for magnet 6K is the same as that previously traced in Figs. 1a and 12) except that it includes, in addition, contact I83 of lever I2LV.

When lever 6V reaches its 1" position, a pick-up circuit is closed for relay 6RP which is the same asthe pick-up circuit previously traced in Figs. 1a and 1b except that it includes, in addition, contact I 84 of lever I2LV. With relay BRP energized, current of reverse polarity is supplied through the front points of contacts 50 and 61 of relay 6R]? to a circuit which is the same as the circuit previously traced through the front points of these contacts in Figs. la and lb except that it includes, in addition front points of contacts of relay LP.

With relay 2F now energized by current of reverse polarity, block lamp 2b will be light-ed, and contact SI of relay 2F will be closed in a circuit for energizinglock magnet 2K which is the same as the circuit for lock magnet 2K previously traced in connection with Figs. la and lb except that it includes contact I83 of lever IBILV in addition.

When the leverman at the west interlocking plant now reverses lever 2V, the eastbound traffic control circuit will be completed similarly to the manner described in Figs. la and lb. With the eastbound traflic control circuit closed, if. a train is to move off of siding D onto track X, the leverman at the west interlocking plant will effect energization of relay IIlL-R, by moving lever IDLV to its r position, similarly to the manner described for energizing relay IZLR when the westbound traflic control circuit was closed.

In Figs. 4a and 4b, the normal or westbound trafiic control circuit is closed, and is the same as described for Figs. 3a and 3b except that it includes a contact !85 of lever I2LV instead of resistor IE2. The circuit for switch repeater relay LP is the same as in Figs. 3a and 3b.

I shall assume that, with apparatus of the form shown in Figs. 4a and 4b, and with the normal traffic control circuit closed, a train is to move from siding D onto track X. A trainman will, therefore, remove bow I'M of padlock P from the electric switch lock of switch Z, causing relay LP to be deenergized as previously described.

A circuit will therefore be completed for relay IZLR which is the same as the circuit previously traced for relay IZLR, in Figs. 3a and 31) except that it includes contact I85 of lever IZLV instead of resistor I52, and includes a condenser I86 in series with the winding of relay IZLR. With condenser I86 in the circuit, constant direct current will not flow for energizing relay 6BR which will thereupon release its front contacts, and relay IZLR will not pick up its front contacts.

With relay 6BR, deenergized, block lamp 6b will be extinguished. The leverman in the east interlocking plant will then reverse lever I2LV.

The circuit for energizing lock magnet 6K is.

the same as previously described in Figs. 3c and 3?) except that it includes, in addition, contact I90 of relay ECTPP.

Lever IZLV, upon leaving its 11 position, opens its contact I84 in the pick-up circuit for relay IERP, and opens its contact I83 in the energizing circuit for lock magnet 8K. At the same time, contact I85 of lever IZLV is opened in the circuit previously described which includes relay I2LR and condenser I86.

When lever IZLV reaches its 1' position, its contacts I6? and I8? close. Contact I81 completes a circuit for energizing code transmitting device ECT, this circuit passing from terminal B, through contact I81 of lever I2LV, and the winding of code transmitter ECT to terminal N.

During the periods when code transmitter ECT closes its contact I88, the code repeating relay ECTP is energized by a circuit passing from terminal B through contact I8'I of lever IZLV, relay I88 of code transmitter ECT and the winding of relay ECTP to terminal N. During the periods when contact I39 of relay ECTP is closed at its back point while relay ECTP is following code transmitter ECT, slow pick-up relay ECTPP' is energized by a circuit passing from terminal ZFB,

through the back point of contact Hi9 of relay ECTP, and the winding of relay ECTPP to terminal ZFN. Since relay ECTPP is of the slow pick-up type, its contact I remains open while contact I89 of relay ECTP is periodically closing alternately at its front and back points.

During the periods when contact I89 of relay EC'IP is closed at its front point, a circuit'is completed for energizing relay IZLR, passing from terminal 2FB, through the front point of contact I89 of relay ECTP, contact IB'I of lever IZLV, and thence by a circuit path which is the same as the circuit previously traced in Figs. 3a and 3b beyond resistor I62 except that it includes a condenser I98 in series with the winding of relay IZLR. Relay IZLR, being of the code following type, will periodically close its contact I93 alternately at the front and back points.

During the periods when contact I93 of relay I2LR is closed at its front point, relay FSA be comes energized by a circuit passing from terminal B, through the back point of contact I92 of relay IBLR, front point of contact I93 of relay I2LR, and the winding of relay FSA in multiple with a resistor I and an asymmetric unit I93 in the high resistance direction to terminal N. During the periods when contact I93 of relay I2LR is closed at its back point, relay BSA will then be energized by a circuit passing from terminal B, through the back point of contact I92 of relay IIILR, back point of contact I93 of relay I ZLR, contact I94 of relay FSA, and the winding of relay BSA in multiple with a resistor I95 and an asymmetric unit I95 in the high resistance direction to terminal N.

With relay BSA energized, a circuit is completed for energizing switch lock magnet WL,

this circuit passing from terminal B, through contact I91 of relay BSA, contact 189 operated by bow I I4 of padlock P, and lock magnet WL to terminal N. Lever IIl-I2V can then be moved to its 1 position for unlocking switch Z as previously described.

I have described the operation of the apparatus for a few typical train movements. In view of the foregoing description, it is believed that the operation of the apparatus for any other possible traffic movement can be readily followed by reference to the drawings.

Although I have herein shown and described only a few forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In traffic locking apparatus for a stretch of railway track including a traffic lever in an interlocking machine for each end of said stretch each having normal and reverse contacts closed in normal and reverse positions respectively of their lever, the combination comprising, a reverse stick relay and a normal stick relay for each of said trafiic levers, a second normal stick relay for one of said traffic levers and a second reverse stick relay for the second traffic lever, a polar stick traffic relay for each of said trafiic levers, a pick-up and a stick circuit for the first normal stick relay for said first traffic lever each controlled by a reverse contact of the associated polar stick relay and said pick-up circuit also controlled by a normal contact of said first traffic lever and by a front contact of the associated reverse stick relay, a pick-up circuit for the re- 21 verse stick relay for said first traffic lever controlled by a reverse contact of said first traflic lever, a stick circuit for the reverse stick relay for said first traffic lever controlled by a back contact of the first normal stick relay for said first traflic lever, a pick-up circuit for said second normal stick relay controlled by a normal contact of the associated polar stick relay, a stick circuit for said second normal stick relay controlled by a back contact of the associated first normal stick relay, an electric lock for said first traffic lever which when deenergized locks said first trafiic lever in its normal or its reverse position, means controlled by a front contact of said second normal stick relay and by a reverse contact of the associated polar stick relay for energizing said electric lock, means controlled by said second traffic lever and by its associated polar stick traflic relay for controlling its normal and reverse stick relays, and means controlled by the first normal stick relay for said first traffic lever and by the first reverse stick relay for said second traffic lever for controlling said polar stick trafiic relays.

2. In tramc locking apparatus for a stretch of railway track including a traffic lever in an interlocking machine for each end of said stretch each having normal and reverse contacts closed in normal and reverse positions respectively of their lever, the combination comprising, a reverse stick relay and a normal stock relay for each of said traffic levers, a second normal'stick relay for one of said traflic levers and a second reverse stick relay for the second trafiic lever, a polar stick traffic relay for each of said traffic levers, a pickup and a stick circuit for the first reverse stick relay for said second traflic lever each controlled by a normal contact of the associated polar stick relay and the pick-up circuit also controlled by a reverse contact of said second trafiic lever and by a front contact of the associated normal stick relay, a pick-up circuit for the normal stick relay for said second trafiic lever controlled by a normal contact of said second traiiic lever, a stick circuit for the normal stick relay for said second trafilc lever controlled by a back contact of the first reverse stick relay for said second traflic lever, a pick-up circuit for said second reverse stick relay controlled by a reverse contact of its associated polar stick relay, a stick circuit for said second reverse stick relay controlled by a back contact of the associated first reverse stick relay, an electric lock for said second traffic lever which when deenergized locks said second traffic lever in its normal or its reverse position, 'means controlled by a front contact of said second reverse stick relay and by a normal contact of the associated polar stick relay for energizing said electric lock, means controlled by sai first traffic lever and by its polar stick traffic relay for controlling its normal and reverse stick relays, and means controlled by the first normal stick relay for said first trailic lever and by the first reverse stick relay for said second traffic lever for controlling said polar stick traffic relays.

3. In traffic locking apparatus for a stretch of railway track including a trafiic lever in an interlocking machine for each end of said stretch each having normal and reverse contacts closed in normal and reverse positions respectively of their lever, the combination comprising, a reverse stick relay and a normal stick relay for each of said trafiic levers, a polar stick traflic relay for each of said trafiic levers, a pick-up and a stick circuit for the normal stick relay for a first one of said traflic levers each controlled by a reverse con tact of the associated polar stick relay and said pick-up circuit also controlled by a normal contact of said first traffic lever and by a front contact of the associated reverse stick relay, a pickup circuit for the reverse stick relay for said first trafiic lever controlled by a reverse contact of said first trafiic lever, a stick circuit for the reverse'stick relay for said'first traffic lever controlled by a back contact of the normal stick relay for said first trafiic lever, an electric lock for said first traffic lever which when de'energized locks said first trafiic lever in its normal or its reverse position, means controlled by a back contact of the normal stick relay for said first traific lever and by a reverse contact of the associated polar stick relay for energizing said electric lock, means controlled by the second traflic lever and by its polar stick trafiic relay for controlling its normal and reverse stick relays, and means controlled by the normal stick relay for said first traffic lever and by the reverse stick relay for said second traffic lever for controlling said polar stick trafiic relays.

4. In traflic locking apparatus for a stretch of railway track including a traflic lever in an interlocking machine for each end of said stretch each having normal and reverse contacts closed in normal and reverse positions respectively of their lever, the combination comprising, a reverse stick relay and a normal stick relay for each of said trafiic levers, a polar stick traific relay for each of said traffic levers, a pick-up and a stick circuit for the reverse stick relay for a second one of said traffic levers each controlled by a normal contact of the associated polar stick relay and the pick-up circuit also controlled by a reverse contact of said second traffic lever and by a front contact of the associated normal stick relay, a pick-up circuit for the normal stick relay for said second traflic lever controlled by a normal contact of said second traffic lever, a stick circuit for the normal stick relay for said second trafiic lever controlled by a back contact of the reverse stick relay'for said second traffic lever, an electric lock for said second traflic lever which when deenergized locks said second traffic lever in its normal or its reverse position, means controlled by a back contact of the reverse stick relay for said second traffic lever and by a normal contact of the associated polar stick relay for energizing said electric lock, means controlled by the first trailic lever and by its polar stick trafiic relay for controlling its normal and reverse stick relays, and means controlled by the normal stick relay for said first traific lever and by the reverse stick relay for said second trafiic lever for controlling said polar stick trafiic relays.

5. In trafiic locking apparatus for a stretch of railway track including a traflic lever for each end of said stretch each having a normal and a reverse position, the combination comprising, a polar stick traflic'relay for each of said traific levers, a normal stick relay for one of said trafiic levers, a reverse stick relay for the other of said traflic levers, means controlled by said one lever in its reverse position for closing a contact which remains closed a brief period of time after said one lever is returned to its normal position, a pick-up'circuit for said normal stick relay controlled by said contact and by said one lever in its normal position and also by a reverse contact of the polar stick traflic relay for said one trafflc lever, a stick circuit for said normal stick relay controlled by a reverse contact of the polar 23 stick relay for said one traffic lever, means controlled by said other trafilc lever and by its. polar stick trafiic relay for controlling said reverse stick relay, and means controlled by said normal and reverse stick relays for controlling said polar stick traflic relays.

6. In trafiic locking apparatus for a stretch of railway track including a traific lever for each end of said stretch each having a normal and a reverse position, the combination comprising, a polar stick tra-fiic relay for each of said trafiic levers, a normal stick relay for one of said trafiic levers, a reverse stick relay for the other of said trafl'ic levers, means controlled by said other lever in its normal position for closing a contact which remains closed a brief period of time after said other lever is operated to its reverse position, a pick-up circuit for said reverse stick relay controlled by said contact and by said other lever in its reverse position and also by a normal contact of the polar stick relay for said other trafiic lever, a stick circuit for said reverse stick relay controlled by a normal contact of the polar stick relay for said other traific lever, means controlled by said one trafiic lever and by its polar stick trafiic relay for controlling said normal stick relay, and means controlled by said normal and reverse stick relays for controlling said polar stick traffic relays.

7. In traflic locking apparatus for a stretch of railway track including a trafiic lever for each end of said stretch each having a normal and a. reverse position, the combination comprising, a polar stick traffic relay for each of said trafiic levers, a normal stick relay for one of said traffic levers, a reverse stick relay for the other of said traffic levers, a normal repeater relay for each of said polar stick relays each controlled by a normal contact of its polar stick relay, a reverse repeater relay for each of said polar stick relays each controlled by a reverse contact of its polar stick relay, a pick-up and a stick circuit for said normal stick relay each controlled by a front contact of the reverse repeater relay for the polar stick relay for said one lever and the pick-up circuit also controlled by said one lever for a brief period of time when said one lever is moved from its reverse to its normal position, a pick-up and a stick circuit for said reverse stick relay each controlled by a front contact of the normal repeater relay for the polar stick relay for said other lever and the pick-up circuit also controlled by said other lever for a brief period of time when said other lever is moved from its normal to its reverse position, and means controlled by said normal and reverse stick relays and by said normal and reverse repeater relays for controlling said polar stick relays.

8. In traflic locking apparatus for a stretch of railway track including a trafiic lever for each end of said stretch each having a normal and a reverse position, the combination comprising, a polar stick traffic relay for each of said traffic levers, a normal stick relay for one of said trafiic levers, a reverse stick relay for the other of said traffic levers, a normal repeater relay for each of said polar stick relays each controlled by a normal contact of its polar stick relay, a reverse repeater relay for each of said polar stick relays each controlled by a reverse contact of its polar stick relay, pick-up and stick circuits for said normal stick relay controlled by said one lever and by the reverse repeater for its polar stick relay, pick-up and stick circuits for said reverse stick relay controlled by said'other lever and by the normal-repeater for its polar stick relay, and normal and reverse control circuits for said polar stick relays controlled by'said normal and reverse stick relays and by said normal and reverserepeater relays.

9. In traffic locking apparatus for a stretch of railway track including a traflic lever for each end of said stretch each having a normal and a reverse position, the combination comprising, a polar stick traffic relay for each of said traffic levers, an electric lock for each of said traflic levers which when deenergized locks its traiiic lever in the normal or the reverse position, a code transmitter for one end of said stretch energized by a circuit controlled by a. normal contact of the lever for that end of said stretch and by a reverse contact of its polar stick tra-fiic relay, a code transmitter for the other end of said stretch energized by a circuit controlled by a reverse contact of the lever for that end of said stretch and by a normal contact of its polar stick traflic relay, a control circuit path including the windings of said polar stick traffic relays in series, means controlled over said control circuit path by each of said code transmitters for energizing the electric lock for the traffic lever at the opposite end of said stretch, and means controlled by both said levers in the normal position or by both said levers in the reverse position for energizing said polar stick traffic relays by current of normal or reverse polarity respectively.

10. In traffic locking apparatus for a stretch of railway track including a traffic lever for each end of said stretch each having a normal and a reverse position, the combination comprising, a pair of control conductors, a polarized trafiic relay for each of said trafiic levers connected in series with each other through said conductors, an electric lock for each of said traffic levers each of which when deenergized locks its traffic lever in the normal or the reverse position, a source of current connected through normal contacts of one of said levers across one end of said pair of conductors, a second source of current connected through reverse contacts of the other lever across the other end of said pair of conductors in opposition to said first source of current, a first code transmitter controlled by a normal contact of said one lever and by a reverse contact of its polarized trafiic relay for at times periodically closing a shunt path across said conductors adjacent said one end of said pair of conductors, a code following relay connected in series with one of said conductors between said shunt path and said one end of said pair of conductors, a second code transmitter controlled by a reverse contact of said other lever and by a normal contact of its polarized trafiic relay for at times periodically closing a second shunt path across said conductors adjacent said other end of said pair of conductors, a second code following relay connected in series with one of said conductors between said second shunt path and said other end of said pair of conductors, means controlled by each of said code following relays for energizing the electric lock for the lever for its end of said stretch when the code transmitter for the opposite end of said stretch is being operated, and means controlled by both said levers in the normal position and by both said levers in the reverse position for energizing said polarized relays by current of normal and reverse polarity respectively.

11. In trafiic locking apparatus for a stretch 

